The described aspects relate generally to wireless communication systems. More particularly, the described aspects relate to techniques for handover procedure management.
Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems. These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level.
An example of an emerging telecommunication standard is Long Term Evolution (LTE). LTE is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by Third Generation Partnership Project (3GPP). It is designed to better support mobile broadband Internet access by improving spectral efficiency, lower costs, improve services, make use of new spectrum, and better integrate with other open standards using OFDMA on the downlink (DL), SC-FDMA on the uplink (UL), and multiple-input multiple-output (MIMO) antenna technology. However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in LTE technology. Preferably, these improvements should be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.
In wireless communication systems employing LTE, when a UE is in communication with a source base station but in the process of, for example, being handed over to a target base station, the UE may transmit relevant information over a physical random access channel (PRACH) for the target base station to determine timing information associated with the UE, e.g., timing advance (TA) for the UE. A procedure involving transmission of the relevant information over a PRACH may cause significant latency in the handover procedure. Added latency to a handover procedure may, for example, result in service interruption during the procedure.
Therefore, there is a desire for techniques that reduce latency when the UE is handed over from the source base station to the target base station.